Swivel Knife Blade Issue

[TomG]

I have 3 swivel knives that I have picked up with used tool purchases at various times. 2 are standard handles with the larger blades and the 3rd is an adjustable with a smaller angle blade.

I have stropped the fire out of them and they have mirror-like faces. One of the standard blades cuts like it's going through butter. The other 2 (standard and angle) feel like they are sort of dragging. --- as if the leather was too dry. But I don't think it is since the 1st knife cuts so smoothly. They just feel rough as they cut.

I have examined them and the only difference I can see is that the smooth cutting blade has a bit of a steeper pitch to it, ie, it has a longer face, than the other 2.

I wouldn't think that it would make a difference this way, but what else could cause it to cut rough?

Thanks

Tom

[TwinOaks]

Take a magnified look at the edge of the blade. You may need to put them on a stone to remove a burr at the edge. The burr is caused by sharpening away from the edge (pulling the blade) and leaving a VERY thin edge that rolls or curls over. To cure it, you just need to follow the bevel and sharpen INTO the edge.....lightly. This will remove the burr and leave you with a 'solid' edge. Then re-strop. You may also have some micro-serrations/ gaps on the cutting edge. Do the same thing to repair it. Use the finest stone you have- I use a diamond sharpener that feels absolutely smooth, and only a few strokes to wear off the burr (when I find one).

[TomG]

Take a magnified look at the edge of the blade. You may need to put them on a stone to remove a burr at the edge. The burr is caused by sharpening away from the edge (pulling the blade) and leaving a VERY thin edge that rolls or curls over. To cure it, you just need to follow the bevel and sharpen INTO the edge.....lightly. This will remove the burr and leave you with a 'solid' edge. Then re-strop. You may also have some micro-serrations/ gaps on the cutting edge. Do the same thing to repair it. Use the finest stone you have- I use a diamond sharpener that feels absolutely smooth, and only a few strokes to wear off the burr (when I find one).

Well, I sort of THINK I see some roughish spots. But I don't see any ridges or rolls.. Nor can I feel them.

I'll keep stropping for a while and see if it helps.

Which side is best to use with the rouge? Flesh or grain side of the leather?

Also, when should I add more rouge? As I strop, the surface of the leather/rouge turns black. Is this OK?

Tom

Edited May 29, 2011 by TomG

[TwinOaks]

If you don't have the steel cut to where it should be, then stropping won't help you. You have to make sure you have the correct angle and a good edge before stropping. The stropping polishes the blade (that's the black stuff you see- minute metal particles) but in very tiny amounts. You could eventually get a sharp blade with it, but you'd probably prefer to have it done sooner than later.

If you put the rouge on leather, use the flesh side. Better yet, use cardboard from the back of a notebook, or cereal box, (or Fedex envelope) and put it on a counter top, then put the rouge on that. Since it's flatter and harder, you're less likely to press too hard and round the edge of the blade. Instead of adding more rouge when the strop is completely loaded, just get a new piece of cardboard.